Obama said recently that he would rather be a good one term president than a mediocre two termer. This reflects a rare moment of reality for the embattled president who at one point told a Blue Dog Democrat expressing fears about this November that the difference between 1994 (when Republicans swept into control of Congress) and 2010 is that "now you have me." He forgot that he has not accomplished anything thus far that would define him as a "good" president. This remark may have been a shot at both of his predecessors, George W. Bush and Bill Clinton (whom he personally seems to despise and vice versa.)
If events continue as they have, Democrats will start mulling a run at the nomination. They will each try to present themselves as the anti-Obama, perhaps event to the extent of looking a little less polished if it leads to the impression of greater substance.
First and foremost, the best Democratic alternative to four more years of Nobama is the sitting secretary of state. Under George W. Bush this was the most honored office in his Cabinet. Condoleeza Rice has tremendous power and latitude. Hillary Clinton goes to town hall meetings in the Congo and begs money off of the Chinese while others handle major affairs separately. This has to grate on her. I would not be surprised to see Clinton resign in the next six to nine months. This would signal to the world that the Democratic nomination is up for grabs. Then it would be the battle of the Chicago Obama organization versus the Clintonistas. The difference between the two is that the Clintons have actually accomplished things.
How about a prominent Democratic governor? The fact is that in this group Joe Manchin has as much credibility as anyone. He has managed to maintain a stable face on state finances while other governments have gotten into trouble. Some may remember his exposure during the Sago mine disaster. Manchin looks, sounds, and acts more like the Clinton prototype than Obama, a fact that could win him credit with Clintonistas if their own hero passes.
The fact is that Obama is weak and stubbornly refuses to adapt his tone, policies, or actions. This adds up to a strong challenge in 2012 from his own party.